Bu çalışma bir BU / CIMIT Uygulamalı Sağlık Mühendisliği predoctoral Bursu, Mühendislik Katılımı Araştırma Başlatma Grant (Brige) genişleten bir Ulusal Bilim Vakfı ve Ulusal Sağlık Enstitüleri (R21EB0094930) tarafından desteklenmiştir.

1. Faz kaydırmalı Nanoemulsion hazırlanması (PSNE) <ol><li> 11 mg DPPC ve kloroform içinde 1.68 mg DSPE-PEG2000 eritilir </li><li> Bir cam yuvarlak tabanlı şişeye kuru bir lipid film oluşturmak için organik çözücü buharlaştırılır </li><li> Gecede lipid filmi Dessicate </li><li> Fosfat-tamponlu salin (PBS) ve 5.5 ml lipid filmi rehidrate </li><li> 45 ° C su banyosunda Isı çözümü lipid filmi periyodik vorteks, eriyene kadar </li><li> 7 ml flakon içine lipid çözümü aktarın </li><li> % 20 genlik 2 dakika süreyle lipid çözelti sonikasyon </li><li> 2.5 ml&#39;lik iki şişe içine çözümü bölün, her (kalan 0.5 ml atmak) </li><li> Her flakon 2.5 ml PBS ekleyin </li><li> A 0 ° C&#39;de buz-su banyosu içinde her şişeye yerleştirin </li><li> Her bir şişeye 50 ul ekle DDFP </li><li> % 25 genlik, pulsed (50 sn kapalı 10 sn), zaman 60 sn toplam: Aşağıdaki ayarları kullanarak buz-su banyosunda her flakon sonikasyon </li><li> Tr20 ml sintilasyon şişeleri için ansfer PSNE çözümler </li><li> 10 ml nihai hacim ile sonuçlanan, her şişeye 5 ml PBS ekleme </li><li> Üretici tarafından sağlanan ekstruder aşağıdaki tarifi birleştirin <ol><li> Deiyonize su ile her bir kısım Durulama </li><li> Filtre destek tabanının merkezinde, paslanmaz çelik destek diski yerleştirin </li><li> Paslanmaz çelik destek diski üzerinde paslanmaz çelik elek yerleştirin </li><li> Cımbız kullanarak, paslanmaz çelik hasır üzerine bir ekstrüder tahliye diski membran (parlak tarafı yukarı) yerleştirin </li><li> Cımbız kullanarak, drenaj disk membran üzerindeki ekstruder filtresi (parlak tarafı yukarı) yerleştirin </li><li> Dikkatlice filtre üzerinde küçük O-ring yerleştirin ve destek tabanı yukarıda thermobarrel ve ekstruder üst yerleştirin </li><li> Kısmen olanlar her kanat somunu sıkın, sonra tamamen bir alternatif moda elle kanat somunlarını </li><li> Için ekstrüder bağlanBir azot gazı hattı </li><li> En iyi numune portu içine ekstruder, 10 ml deiyonize su hazırlamak için, açılış kap ve havalandırma valfı sıkıştırmak </li><li> Yavaşça zarından örnek zorlayarak, basıncı artırmak için azot gazı hattı açın ve çıkış borudan numune </li><li> Kullanımdan sonra, ters sırada sökülmesi deiyonize su ile ekstruder parçalar durulama ve bir membran filtre, membran boşaltma disk atmak </li></ol></li><li> 200 nm filtresi aracılığıyla 10 kez çekilerek 100 nm damlacıkları için sadece ön koşul PSNE </li><li> Filtre 100 nm veya 200 nm ile Extrude PSNE 16 kez dar boyut dağılımı elde etmek için </li></ol> 2. PSNE İçeren Poliakrilamid Hidrojel hazırlanması <ol><li> 5 ml deiyonize su içinde 1.2 g BSA, toz seyreltilerek% 24 BSA çözeltisi hazırlayın </li><li> 1 mL deiyonize Su sağlama içinde seyreltilmiş 0.1 g APS toz% 10 APS çözelti hazırlayınr </li><li> Aşağıdaki sırada, 2.1 ml akrilamid çözeltisi, 1.2 ml Tris tamponu, 0.1 ml% 10 APS, 4,5 ml% 24 BSA çözeltisi ve plastik bölme içinde 3.6 ml deiyonize su karışımı </li><li> 40 ° Isı, 1 saat boyunca vakum altına C ve yer </li><li> PSNE 480 ul ekleyin ve iyice yavaşça plastik odasına dönen tarafından karıştırın. </li><li> 12 ul TEMED ilave edin ve 2 saat için bir 12 ° C su banyosu içinde oda yerleştirmek </li></ol> 3. Temsilcisi Sonuçlar Doku taklit eden hidrojel fantom ile ultrason deneyler için bir düzeneğin şematik Şekil 1 &#39;de gösterilmiştir. Bu protokol, en azından bir hafta için çözelti içinde kararlı olan dar bir boyut dağılımı ile kaplanmış perfluorokarbonlar lipid damlacıkları ile sonuçlanır. Dinamik ışık saçılımı (90Plus Parçacık Boyutu Analiz Cihazı, Brookhaven Instruments, Holtsville, NY) ile ölçülen büyüklük dağılımı PSNE ekstrüde 100 ve 200 kullanımı için, Şekil 2 &#39;de gösterilmiştirnm filtreler. Dinamik ışık saçılımı kullanılarak ölçülen zamanla PSNE etkin çapı, PSNE en az bir hafta boyunca istikrarlı olduğunu gösteren Tablo 1&#39;de listelenmiştir. Bir poliakrilamid hidrojel içinde buharlaştırma önce ve sonra PSNE B-mod görüntü Şekil 3 &#39;de gösterilmiştir. Ayrıca, bir lezyon albümin ve PSNE Şekil 4 de gösterilmiştir içeren bir poliakrilamid hidrojel HIFU-aracılı ısıtma 15 saniye ile oluşmuştur. Lezyonun asimetrik şekli ultrason yol içinde kabarcık bulut varlığı nedeniyle oluşur prefocal ısıtma bir sonucudur. Bu iletilen akustik güç azaltarak minimize edilebilir prefocal ısıtma ve baloncuklar gelen dağılım nedeniyle lezyon oluşumu dikkat etmek önemlidir. <img src="/files/ftp_upload/4308/4308fig1.jpg" alt="Şekil 1"/> Şekil 1. Doku-mim ile ultrason deneyler için deney düzeneği şematik diyagramıhidrojeller Icking. <img src="/files/ftp_upload/4308/4308fig2.jpg" alt="Şekil 2,"/> Şekil 2. Boyut 100 nm veya 200 nm filtreler aracılığıyla çekilmiş PSNE dağıtımı, dinamik ışık saçılımı kullanılarak ölçülür. Ordinat eksenlerinin birimleri numuneden toplam dağınık ışık yoğunluğuna göre belli bir boyuttaki parçacıklar gelen dağınık ışık yoğunluğunu dayanmaktadır. <img src="/files/ftp_upload/4308/4308fig3.jpg" alt="Şekil 3"/> Şekil 3,. B-mod görüntüleri bir poliakrilamid hidrojel PSNE buharlaşma (a) daha önce ve (b) sonra. Ok bir baloncuk bulut PSNE buharlaşma tarafından kuruldu fokal bir bölgenin gösterir. <img src="/files/ftp_upload/4308/4308fig4.jpg" alt="Şekil 4,"/> Polyacr Şekil 4. Görüntüleralbümin ve PSNE içeren ilamit hidrojel (a) &#39;HIFU buharlaştırma ve sonikasyon önce ve (b) sonra, ultrason ile endüklenen ısıtma sonucu olarak lezyon oluşumu ortaya koydu. Ultrason merkez frekansı 3.3 MHz idi. Ultrason sinyali ilk 30 döngü oluşuyordu, 6.4 W darbe PSNE buharlaştırmak için hemen W. 0.77 sürekli ultrason 15 sn izledi <table border="1"><tbody><tr><td rowspan="2"> Ekstrüzyon sonra gün </td><td colspan="2"> 200 nm filtreli Ekstrüde </td><td colspan="2"> 100 nm filtreli Ekstrüde </td></tr><tr><td> Dia ortalama. (Nm) </td><td> Std. Dev. (Nm) </td><td> Dia ortalama. (Nm) </td><td> Std. Dev. (Nm) </td></tr><tr><td> 1 </td><td> 182.9 </td><td> 4.9 </td><td> 118.0 </td><td> 0.9 </td></tr><tr><td> 7 </td> &lt;td&gt; 177.7 </td><td> 2.5 </td><td> 124.8 </td><td> 3.1 </td></tr></tbody></table> Tablo 1. 100 nm ve 200 nm filtreler ile ekstrüzyon ardına ve yedi gün de çapı ve PSNE standart sapma.

<ol>
	<li>Hynynen, K., Darkazanli, A., Unger, E., Schenck, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MRI-guided+noninvasive+ultrasound+surgery.">MRI-guided noninvasive ultrasound surgery.</a> Med. Phys. 20, 107-115 (1993).</li><li>Baban, D. F., Seymour, L. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Control+of+tumour+vascular+permeability.">Control of tumour vascular permeability.</a> Adv. Drug Deliv. Rev. 34, 109-119 (1998).</li><li>Maeda, H., Wu, J., Sawa, T., Matsumura, Y., Hori, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor+vascular+permeability+and+the+EPR+effect+in+macromolecular+therapeutics:+a+review.">Tumor vascular permeability and the EPR effect in macromolecular therapeutics: a review.</a> J. Control. Release. 65, 271-284 (2000).</li><li>Schadlich, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor+accumulation+of+NIR+fluorescent+PEG-PLA+nanoparticles:+impact+of+particle+size+and+human+xenograft+tumor+model.">Tumor accumulation of NIR fluorescent PEG-PLA nanoparticles: impact of particle size and human xenograft tumor model.</a> ACS Nano. 5, 8710-8720 (2011).</li><li>Williams, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Convertible+perfluorocarbon+droplets+for+cancer+detection+and+therapy.">Convertible perfluorocarbon droplets for cancer detection and therapy.</a> 2010 IEEE Ultrasonics Symposium. , (2010).</li><li>Martz, T. D., Sheeran, P. S., Bardin, D., Lee, A. P., Dayton, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Precision+manufacture+of+phase-change+perfluorocarbon+droplets+using+microfluidics.">Precision manufacture of phase-change perfluorocarbon droplets using microfluidics.</a> Ultrasound Med. Biol. 37, 1952-1957 (2011).</li><li>Giesecke, T., Hynynen, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrasound-mediated+cavitation+thresholds+of+liquid+perfluorocarbon+droplets+in+vitro.">Ultrasound-mediated cavitation thresholds of liquid perfluorocarbon droplets in vitro.</a> Ultrasound Med. Biol. 29, 1359-1365 (2003).</li><li>Sheeran, P. S., Luois, S., Dayton, P. A., Matsunaga, T. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formulation+and+Acoustic+Studies+of+a+New+Phase-Shift+Agent+for+Diagnostic+and+Therapeutic+Ultrasound.">Formulation and Acoustic Studies of a New Phase-Shift Agent for Diagnostic and Therapeutic Ultrasound.</a> Langmuir. 27, 10412-10420 (2011).</li><li>Sheeran, P. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Decafluorobutane+as+a+phase-change+contrast+agent+for+low-energy+extravascular+ultrasonic+imaging.">Decafluorobutane as a phase-change contrast agent for low-energy extravascular ultrasonic imaging.</a> Ultrasound Med. Biol. 37, 1518-1530 (2011).</li><li>Zhang, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Application of Phase-Shift Nanoemulsion in High Intensity Focused Ultrasound: An In Vitro Study [Doctoral Dissertation]. , (2011).</li><li>Allen, T. M., Hansen, C., Martin, F., Redemann, C., Yau-Young, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Liposomes+containing+synthetic+lipid+derivatives+of+poly(ethylene+glycol)+show+prolonged+circulation+half-lives+in+vivo.">Liposomes containing synthetic lipid derivatives of poly(ethylene glycol) show prolonged circulation half-lives in vivo.</a> Biochim. Biophys. Acta. 1066, 29-36 (1991).</li><li>Klibanov, A. L., Maruyama, K., Beckerleg, A. M., Torchilin, V. P., Huang, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Activity+of+amphipathic+poly(ethylene+glycol)+5000+to+prolong+the+circulation+time+of+liposomes+depends+on+the+liposome+size+and+is+unfavorable+for+immunoliposome+binding+to+target.">Activity of amphipathic poly(ethylene glycol) 5000 to prolong the circulation time of liposomes depends on the liposome size and is unfavorable for immunoliposome binding to target.</a> Biochim. Biophys. Acta. 1062, 142-148 (1991).</li><li>Klibanov, A. L., Maryama, K., Torchilin, V. P., Huang, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amphipathic+polyethyleneglycols+effectively+prolong+the+circulation+time+of+liposomes.">Amphipathic polyethyleneglycols effectively prolong the circulation time of liposomes.</a> FEBS Lett. 268, 235-237 (1990).</li><li>Gabizon, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prolonged+circulation+time+and+enhanced+accumulation+in+malignant+exudates+of+Doxorubicin+encapsulated+in+polyethylene-glycol+coated+liposomes.">Prolonged circulation time and enhanced accumulation in malignant exudates of Doxorubicin encapsulated in polyethylene-glycol coated liposomes.</a> Cancer Res. 54, 987-992 (1994).</li><li>Awasthi, V. D., Garcia, D., Goins, B. A., Philips, W. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circulation+and+biodistribution+profiles+of+long-circulating+PEG-liposomes+of+various+sizes+in+rabbits.">Circulation and biodistribution profiles of long-circulating PEG-liposomes of various sizes in rabbits.</a> Int. J. Pharm. 253, 121-132 (2003).</li><li>Zhang, P., Porter, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+in+vitro+study+of+a+phase-shift+nanoemulsion:+a+potential+nucleation+agent+for+bubble-enhanced+HIFU+tumor+ablation.">An in vitro study of a phase-shift nanoemulsion: a potential nucleation agent for bubble-enhanced HIFU tumor ablation.</a> Ultrasound Med. Biol. 36, 1856-1866 (2010).</li><li>Lafon, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gel+phantom+for+use+in+high-intensity+focused+ultrasound+dosimetry.">Gel phantom for use in high-intensity focused ultrasound dosimetry.</a> Ultrasound Med. Biol. 31, 1383-1389 (2005).</li></ol>

Çıkar çatışması ilan etti.

Yüksek yoğunluklu odaklanmış ultrason (HIFU) termal tümörleri baskılamak için klinik olarak kullanılmaktadır. 1 lokalize ısıtma geliştirmenize ve tümörlerde termal ablasyon artırmak için, lipid kaplı perflorokarbon damlacıkları HIFU buharlaştınlabilen geliştirilmiştir. Birçok tümörün damar nedeniyle hızlı büyüme anormal sızıntılı olduğunu. Böylece 2, nanopartiküller fenestrasyonlar nüfuz ve pasif tümörler içinde birikir edebiliyoruz, gelişmiş geçirgenli...

<table border="1"><tbody><tr><td> Ortak Ad </td><td> Üretici </td><td> Kedi. Numara </td><td> Tam Adı / Açıklama </td></tr><tr><td> DPPC </td><td> Avanti Lipidler, Alabaster, AL, ABD </td><td> 850355P </td><td> 1,2-dipalmitoil-sn-glisero-3-fosfokolin </td></tr><tr><td> DSPE-PEG2000 </td><td> Avanti Lipidler, Alabaster, AL, ABD </td><td> 880120P </td><td> 1,2-distearoil-sn-glisero-3-phosphoethanolamine-N-[metoksi (polietilen glikol) -2000] (amonyum tuzu) </td></tr><tr><td> DDFP </td><td> Fluoromed, Round Rock, Teksas, ABD </td><td> CAS: 138495-42-8 </td><td> Dodecafluoropentane (C 5 F 12) </td></tr><tr><td> PBS </td><td> Sigma-Aldrich, St Louis, MO, USA </td><td> P2194 </td><td> Salin Fosfat-tamponlu </td></tr><tr><td> Kloroform </td><td> Sigma-Aldrich, St. Louis, MO, USA </td><td> 372978 </td><td> Kloroform </td></tr><tr><td> Akrilamid </td><td> Sigma-Aldrich, St Louis, MO, USA </td><td> A9926 </td><td> % 40 19:01 akrilamid / bis-akrilamid </td></tr><tr><td> Tris tampon </td><td> Sigma-Aldrich, St Louis, MO, USA </td><td> T2694 </td><td> 1 M, pH 8, trizma hidroklorid ve taban trizma </td></tr><tr><td> BSA </td><td> Sigma-Aldrich, St Louis, MO, USA </td><td> A3059 </td><td> Sığır serum albümini </td></tr><tr><td> APS </td><td> Sigma-Aldrich, St Louis, MO, USA </td><td> A3678 </td><td> Amonyum persülfat çözümü </td></tr><tr><td> TEMED </td><td> Sigma-Aldrich, St Louis, MO, USA </td><td> 87689 </td><td> N, N, N &#39;, N&#39;-Tetramethylethylenediamine </td></tr><tr><td></td><td></td><td></td><td> Ekipman </td></tr><tr><td> Sonikatör (3 mm uç) </td&gt; <td> Sonics &amp; Materials, Inc, Newtown, CT, ABD </td><td> Vibra-Cell </td><td></td></tr><tr><td> Su banyosu </td><td> Thermo Fisher Scientific, Waltham, MA, USA </td><td> NESLAB EX-7 </td><td></td></tr><tr><td> Extruder </td><td> Kuzey Lipidler, Burnaby, BC, Kanada </td><td> LIPEX </td><td></td></tr><tr><td> Extruder Filtreler </td><td> Whatman Piscataway, NJ, ABD </td><td> # 110605 ve # 110606 Nuclepore </td><td></td></tr><tr><td> Extruder Tahliye Disk </td><td> Sterlitech Corporation, Kent, WA, ABD </td><td> # PETEDD25100 </td><td></td></tr><tr><td> Plastik odası </td><td> ABD Plastik Corporation, Lima, OH, ABD </td><td> # 55288, 1 3/16 &quot;x1 3/16&quot; x2 7/16 &quot; </td><td></td></tr></tbody></table>

synthesis of phase-shift nanoemulsions with narrow size distributions for acoustic droplet vaporization and bubble-enhanced ultrasound-mediated ablation

Yüksek yoğunluklu odaklanmış ultrason (HIFU) termal tümörleri baskılamak için klinik olarak kullanılmaktadır. Lokal ısıtma artırmak ve tümörlerin termal ablasyon artırmak için, lipid-kaplı perfluorokarbonlar damlacıkları HIFU buharlaştınlabilen geliştirilmiştir. Birçok tümörün damar nedeniyle hızlı büyüme anormal sızdıran ve nanopartiküller fenestrasyonlar nüfuz ve pasif tümörler içinde birikir edebiliyoruz. Böylece, damlacıkların boyutunu denetlemek tümörler içinde daha iyi bir birikim neden olabilir. Bu yazıda, dar bir boyut dağılımı ile bir faz kayması nanoemulsion (PSNE) içinde kararlı damlacıklarının hazırlanması tarif edilmektedir. PSNE sıvı perfluorokarbon varlığında, bir lipid çözelti sonicating sentezlendi. Dar bir büyüklük dağılımı 100 veya 200 nm gözenek boyutlarına sahip filtreler kullanılarak PSNE birçok kez ekstrüzyon ile elde edilmiştir. Boyut dağılımı dinamik ışık saçılımı ile 7 günlük bir süre boyunca ölçüldü. PolyacPSNE içeren rylamide hidrojeller in vitro deneyler için hazırlanmıştır. Hidrojellerde PSNE damlacıkları ultrason ve lokalize ısıtma geliştirilmiş çıkan kabarcıkları ile buharlaştırılır edildi. Buharlaşan PSNE daha hızlı ısıtma sağlar ve ayrıca termal ablasyon için gerekli ultrason yoğunluğunu azaltır. Böylece, PSNE potansiyel HIFU-aracılı termal ablasyon tedavisi terapötik sonuçların iyileştirilmesi, tümörlerde termal ablasyon geliştirmek için bekleniyor.

Watch this Scientific Journal Video about Synthesis of Phase-shift Nanoemulsions with Narrow Size Distributions for Acoustic Droplet Vaporization and Bubble-enhanced Ultrasound-mediated Ablation at Jo

Synthesis of Phase-shift Nanoemulsions with Narrow Size Distributions for Acoustic Droplet Vaporization and Bubble-enhanced Ultrasound-mediated Ablation

Faz kaydırmalı nanoemulsions (PSNE) lokalize ısıtma geliştirmenize ve tümörlerde termal ablasyon geliştirmek için yüksek yoğunluklu odaklanmış ultrason kullanarak buharlaşmış olabilir. Bu yazıda, dar bir boyut dağılımı ile kararlı PSNE hazırlanması tarif edilmektedir. Ayrıca, ultrason aracılı ablasyonu konusunda buharlaşmış PSNE etkisini doku taklidi hayaletleri gösterilmiştir.

Akustik Damlacık buharlaşması ve Bubble-gelişmiş Ultrason aracılı Ablasyon için dar Boyut Dağılımları ile Faz-shift Nanoemulsions sentezi

High-intensity  focused ultrasound (HIFU) is used clinically to thermally ablate tumors. To  enhance localized heating and improve thermal ablation in ...

synthesis-phase-shift-nanoemulsions-with-narrow-size-distributions

Research

JoVE Journal

Engineering

10.9K Görüntüleme.  Boston University. Faz kaydırmalı nanoemulsions (PSNE) lokalize ısıtma geliştirmenize ve tümörlerde termal ablasyon geliştirmek için yüksek yoğunluklu odaklanmış ultrason kullanarak buharlaşmış olabilir. Bu yazıda, dar bir boyut dağılımı ile kararlı PSNE hazırlanması tarif edilmektedir. Ayrıca, ultrason aracılı ablasyonu konusunda buharlaşmış PSNE etkisini doku taklidi hayaletleri gösterilmiştir.

Video: Synthesis of Phase-shift Nanoemulsions with Narrow Size Distributions for Acoustic Droplet Vaporization and Bubble-enhanced Ultrasound-mediated Ablation

Controlling the Size, Shape and Stability of Supramolecular Polymers in Water

For aqueous based supramolecular polymers, the simultaneous control over shape, size and stability is very difficult1. At the same time, the ability to do so is highly important in view of a number of applications in functional soft matter including electronics, biomedical engineering, and sensors. In the past, successful strategies to control the size and shape of supramolecular polymers typically focused on the use of templates2,3, end cappers4 or selective solvent techniques5. 
Here we disclose a strategy based on self-assembling discotic amphiphiles that leads to the control over stack length and shape of ordered, chiral columnar aggregates. By balancing electrostatic repulsive interactions on the hydrophilic rim and attractive non-covalent forces within the hydrophobic core of the polymerizing building block, we manage to create small and discrete spherical objects6,7. Increasing the salt concentration to screen the charges induces a sphere-to-rod transition. Intriguingly, this transition is expressed in an increase of cooperativity in the temperature-dependent self-assembly mechanism, and more stable aggregates are obtained. 
For our study we select a benzene-1,3,5-tricarboxamide (BTA) core connected to a hydrophilic metal chelate via a hydrophobic, fluorinated L-phenylalanine based spacer (Scheme 1). The metal chelate selected is a Gd(III)-DTPA complex that contains two overall remaining charges per complex and necessarily two counter ions. The one-dimensional growth of the aggregate is directed by &pi;-&pi; stacking and intermolecular hydrogen bonding. However, the electrostatic, repulsive forces that arise from the charges on the Gd(III)-DTPA complex start limiting the one-dimensional growth of the BTA-based discotic once a certain size is reached. At millimolar concentrations the formed aggregate has a spherical shape and a diameter of around 5 nm as inferred from 1H-NMR spectroscopy, small angle X-ray scattering, and cryogenic transmission electron microscopy (cryo-TEM). The strength of the electrostatic repulsive interactions between molecules can be reduced by increasing the salt concentration of the buffered solutions. This screening of the charges induces a transition from spherical aggregates into elongated rods with a length &gt; 25 nm. Cryo-TEM allows to visualise the changes in shape and size. In addition, CD spectroscopy permits to derive the mechanistic details of the self-assembly processes before and after the addition of salt. Importantly, the cooperativity -a key feature that dictates the physical properties of the produced supramolecular polymers- increases dramatically upon screening the electrostatic interactions. This increase in cooperativity results in a significant increase in the molecular weight of the formed supramolecular polymers in water.

The goal of this experiment is to determine and control the size, shape and stability of self-assembled discotic amphiphiles in water. For aqueous based supramolecular polymers such level of control is very difficult. We apply a strategy using both repulsive and attractive interactions. The experimental techniques applied to characterize this system are broadly applicable.

Su Supramoleküler Polimerlerin Boyut, Şekil ve Stabilite Kontrolü

For aqueous based supramolecular polymers, the simultaneous control over shape, size and stability is very difficult1. At the same time, the ability to do ...

Mühendislik

Synthesis and Operation of Fluorescent-core Microcavities for Refractometric Sensing

This paper discusses fluorescent core microcavity-based sensors that can operate in a microfluidic analysis setup. These structures are based on the formation of a fluorescent quantum-dot (QD) coating on the channel surface of a conventional microcapillary. Silicon QDs are especially attractive for this application, owing in part to their negligible toxicity compared to the II-VI and II-VI compound QDs, which are legislatively controlled substances in many countries. While the ensemble emission spectrum is broad and featureless, an Si-QD film on the channel wall of a capillary features a set of sharp, narrow peaks in the fluorescence spectrum, corresponding to the electromagnetic resonances for light trapped within the film. The peak wavelength of these resonances is sensitive to the external medium, thus permitting the device to function as a refractometric sensor in which the QDs never come into physical contact with the analyte. The experimental methods associated with the fabrication of the fluorescent-core microcapillaries are discussed in detail, as well as the analysis methods. Finally, a comparison is made between these structures and the more widely investigated liquid-core optical ring resonators, in terms of microfluidic sensing capabilities.

Fluorescent-core microcavity sensors employ a high-index quantum-dot coating in the channel of silica microcapillaries. Changes in the refractive index of fluids pumped into the capillary channel cause shifts in the microcavity fluorescence spectrum that can be used to analyze the channel medium.

Refraktometrik Algılama Floresan çekirdekli mikro kavitasyonlar sentezi ve İşletilmesi

This paper discusses  fluorescent core microcavity-based sensors that can operate in a microfluidic  analysis setup. These structures are based on the ...

Process of Making Three-dimensional Microstructures using Vaporization of a Sacrificial Component

Vascular structures in natural systems are able to provide high mass transport through high surface areas and optimized structure. Few synthetic material fabrication techniques are able to mimic the complexity of these structures while maintaining scalability. The Vaporization of a Sacrificial Component (VaSC) process is able to do so. This process uses sacrificial fibers as a template to form hollow, cylindrical microchannels embedded within a matrix. Tin (II) oxalate (SnOx) is embedded within poly(lactic) acid (PLA) fibers which facilitates the use of this process. The SnOx catalyzes the depolymerization of the PLA fibers at lower temperatures. The lactic acid monomers are gaseous at these temperatures and can be removed from the embedded matrix at temperatures that do not damage the matrix. Here we show a method for aligning these fibers using micromachined plates and a tensioning device to create complex patterns of three-dimensionally arrayed microchannels. The process allows the exploration of virtually any arrangement of fiber topologies and structures.

The Vaporization of a Sacrificial Component (VaSC) process is used to fabricate microvascular structures. This procedure uses sacrificial poly(lactic) acid fibers to form hollow microchannels with precise 3D geometric positioning provided by laser micromachined guide plates.

Bir Kurban bileşeni buharlaşma kullanarak üç boyutlu Mikroyapılar Yapma Süreci

Vascular structures in natural systems are able to provide high mass transport through high surface areas and optimized structure. Few synthetic material ...

Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics

Surface acoustic waves (SAWs) can be used to drive liquids in portable microfluidic chips via the acoustic counterflow phenomenon. In this video we present the fabrication protocol for a multilayered SAW acoustic counterflow device. The device is fabricated starting from a lithium niobate (LN) substrate onto which two interdigital transducers (IDTs) and appropriate markers are patterned. A polydimethylsiloxane (PDMS) channel cast on an SU8 master mold is finally bonded on the patterned substrate. Following the fabrication procedure, we show the techniques that allow the characterization and operation of the acoustic counterflow device in order to pump fluids through the PDMS channel grid. We finally present the procedure to visualize liquid flow in the channels. The protocol is used to show on-chip fluid pumping under different flow regimes such as laminar flow and more complicated dynamics characterized by vortices and particle accumulation domains.

In this video we first describe fabrication and operation procedures of a surface acoustic wave (SAW) acoustic counterflow device. We then demonstrate an experimental setup that allows for both qualitative flow visualization and quantitative analysis of complex flows within the SAW pumping device.

Yüzey-akustik dalga odaklı Akustik-ters akışlı Mikroakiskan Fabrikasyon, İşletme ve Akış Görselleştirme

Surface acoustic waves (SAWs) can be used to drive liquids in portable microfluidic chips via the acoustic counterflow phenomenon. In this video we ...

Characterization of Nanocrystal Size Distribution using Raman Spectroscopy with a Multi-particle Phonon Confinement Model

Analysis of the size distribution of nanocrystals is a critical requirement for the processing and optimization of their size-dependent properties. The common techniques used for the size analysis are transmission electron microscopy (TEM), X-ray diffraction (XRD) and photoluminescence spectroscopy (PL). These techniques, however, are not suitable for analyzing the nanocrystal size distribution in a fast, non-destructive and a reliable manner at the same time. Our aim in this work is to demonstrate that size distribution of semiconductor nanocrystals that are subject to size-dependent phonon confinement effects, can be quantitatively estimated in a non-destructive, fast and reliable manner using Raman spectroscopy. Moreover, mixed size distributions can be separately probed, and their respective volumetric ratios can be estimated using this technique. In order to analyze the size distribution, we have formulized an analytical expression of one-particle PCM and projected it onto a generic distribution function that will represent the size distribution of analyzed nanocrystal. As a model experiment, we have analyzed the size distribution of free-standing silicon nanocrystals (Si-NCs) with multi-modal size distributions. The estimated size distributions are in excellent agreement with TEM and PL results, revealing the reliability of our model.

We demonstrate how to determine the size distribution of semiconductor nanocrystals in a quantitative manner using Raman spectroscopy employing an analytically defined multi-particle phonon confinement model. Results obtained are in excellent agreement with the other size analysis techniques like transmission electron microscopy and photoluminescence spectroscopy.

Multi-parçacık Phonon Confinement Modeli ile Raman Spektroskopisi kullanarak nano-kristal Boyut Dağılımı Karakterizasyonu

Analysis of the size distribution of nanocrystals is a critical requirement for the processing and optimization of their size-dependent properties. The ...

Characterization of Full Set Material Constants and Their Temperature Dependence for Piezoelectric Materials Using Resonant Ultrasound Spectroscopy

During the operation of high power electromechanical devices, a temperature rise is unavoidable due to mechanical and electrical losses, causing the degradation of device performance. In order to evaluate such degradations using computer simulations, full matrix material properties at elevated temperatures are needed as inputs. It is extremely difficult to measure such data for ferroelectric materials due to their strong anisotropic nature and property variation among samples of different geometries. Because the degree of depolarization is boundary condition dependent, data obtained by the IEEE (Institute of Electrical and Electronics Engineers) impedance resonance technique, which requires several samples with drastically different geometries, usually lack self-consistency. The resonant ultrasound spectroscopy (RUS) technique allows the full set material constants to be measured using only one sample, which can eliminate errors caused by sample to sample variation. A detailed RUS procedure is demonstrated here using a lead zirconate titanate (PZT-4) piezoceramic sample. In the example, the complete set of material constants was measured from room temperature to 120 &#176;C. Measured free dielectric constants <img alt="Equation 1" src="/files/ftp_upload/53461/image001.jpg" /> and&#160;<img alt="Equation 2" src="/files/ftp_upload/53461/image002.jpg" /> were compared with calculated ones based on the measured full set data, and piezoelectric constants d15 and d33 were also calculated using different formulas. Excellent agreement was found in the entire range of temperatures, which confirmed the self-consistency of the data set obtained by the RUS.

This protocol describes the procedure of measuring the temperature dependence of the full set material constants of piezoelectric materials using resonant ultrasound spectroscopy (RUS).

Tam Set Malzeme sabitleri Karakterizasyonu ve rezonans Ultrason Spektroskopisi kullanarak Piezoelektrik Malzemelerin Onların Sıcaklık Bağımlılığı

During the operation of high power electromechanical devices, a temperature rise is unavoidable due to mechanical and electrical losses, causing the ...

Capillary-based Centrifugal Microfluidic Device for Size-controllable Formation of Monodisperse Microdroplets

Here, we demonstrate a simple method for the rapid production of size-controllable, monodisperse, W/O microdroplets using a capillary-based centrifugal microfluidic device. W/O microdroplets have recently been used in powerful methods that enable miniaturized chemical experiments. Therefore, developing a versatile method to yield monodisperse W/O microdroplets is needed. We have developed a method for generating monodisperse W/O microdroplets based on a capillary-based centrifugal axisymmetric co-flowing microfluidic device. We succeeded in controlling the size of microdroplets by adjusting the capillary orifice. Our method requires equipment that is easier-to-use than with other microfluidic techniques, requires only a small volume (0.1-1 &#181;l) of sample solution for encapsulation, and enables the production of hundreds of thousands number of W/O microdroplets per second. We expect this method will assist biological studies that require precious biological samples by conserving the volume of the samples for rapid quantitative analysis biochemical and biological studies.

Here, we demonstrate a simple production method for size-controllable, monodisperse, water-in-oil (W/O) microdroplets using a capillary-based centrifugal microfluidic device. This method requires only a small sample volume and enables high-yield production. We expect this method will be useful for rapid biochemical and cellular analyses.

Tek dağılımlı mikro damlacıklar boyutu kontrollü Formasyonu için Kılcal tabanlı Santrifüj mikroakışkan Cihaz

Here, we demonstrate a simple method for the rapid production of size-controllable, monodisperse, W/O microdroplets using a capillary-based centrifugal ...

Fabrication and Operation of Acoustofluidic Devices Supporting Bulk Acoustic Standing Waves for Sheathless Focusing of Particles

Acoustophoresis refers to the displacement of suspended objects in response to directional forces from sound energy. Given that the suspended objects must be smaller than the incident wavelength of sound and the width of the fluidic channels are typically tens to hundreds of micrometers across, acoustofluidic devices typically use ultrasonic waves generated from a piezoelectric transducer pulsating at high frequencies (in the megahertz range). At characteristic frequencies that depend on the geometry of the device, it is possible to induce the formation of standing waves that can focus particles along desired fluidic streamlines within a bulk flow. Here, we describe a method for the fabrication of acoustophoretic devices from common materials and clean room equipment. We show representative results for the focusing of particles with positive or negative acoustic contrast factors, which move towards the pressure nodes or antinodes of the standing waves, respectively. These devices offer enormous practical utility for precisely positioning large numbers of microscopic entities (e.g., cells) in stationary or flowing fluids for applications ranging from cytometry to assembly.

Acoustofluidic devices use ultrasonic waves within microfluidic channels to manipulate, concentrate and isolate suspended micro and nanoscopic entities. This protocol describes the fabrication and operation of such a device supporting bulk acoustic standing waves to focus particles in a central streamline without the aid of sheath fluids.

Fabrikasyon ve Acoustofluidic Cihazlarının Çalışma Parçacıkların yoğunlaşırken Sheathless için Toplu Akustik Daimi Dalgalar desteklenmesi

Acoustophoresis refers to the displacement of suspended objects in response to directional forces from sound energy. Given that the suspended objects must ...

Measuring Spray Droplet Size from Agricultural Nozzles Using Laser Diffraction

When making an application of any crop protection material such as an herbicide or pesticide, the applicator uses a variety of skills and information to make an application so that the material reaches the target site (i.e., plant). Information critical in this process is the droplet size that a particular spray nozzle, spray pressure, and spray solution combination generates, as droplet size greatly influences product efficacy and how the spray moves through the environment. Researchers and product manufacturers commonly use laser diffraction equipment to measure the spray droplet size in laboratory wind tunnels. The work presented here describes methods used in making spray droplet size measurements with laser diffraction equipment for both ground and aerial application scenarios that can be used to ensure inter- and intra-laboratory precision while minimizing sampling bias associated with laser diffraction systems. Maintaining critical measurement distances and concurrent airflow throughout the testing process is key to this precision. Real time data quality analysis is also critical to preventing excess variation in the data or extraneous inclusion of erroneous data. Some limitations of this method include atypical spray nozzles, spray solutions or application conditions that result in spray streams that do not fully atomize within the measurement distances discussed. Successful adaption of this method can provide a highly efficient method for evaluation of the performance of agrochemical spray application nozzles under a variety of operational settings. Also discussed are potential experimental design considerations that can be included to enhance functionality of the data collected.

We present protocols to be used in the measurement of spray droplet size from agricultural nozzles used in both aerial and ground based agrochemical applications. These methods presented were developed to provide consistent and repeatable droplet size data both inter- and intra-laboratory, when using laser diffraction systems.

Lazer difraksiyonu kullanılarak tarım memelerden Ölçüm Sprey damlacık boyutu

When making an application of any crop protection material such as an herbicide or pesticide, the applicator uses a variety of skills and information to ...

A Pipette-Tip Based Method for Seeding Cells to Droplet Microfluidic Platforms

Amongst various microfluidic platform designs frequently used for cellular analysis, droplet-microfluidics provides a robust tool for isolating and analyzing cells at the single-cell level by eliminating the influence of external factors on the cellular microenvironment. Encapsulation of cells in droplets is dictated by the Poisson distribution as a function of the number of cells present in each droplet and the average number of cells per volume of droplet. Primary cells, especially immune cells, or clinical specimens can be scarce and loss-less encapsulation of cells remains challenging. In this paper, we present a new methodology that uses pipette-tips to load cells to droplet-based microfluidic devices without the significant loss of cells. With various cell types , we demonstrate efficient cell encapsulation in droplets that closely corresponds to the encapsulation efficiency predicted by the Poisson distribution. Our method ensures loss-less loading of cells to microfluidic platforms and can be easily adapted for downstream single cell analysis, e.g., to decode cellular interactions between different cell types.

This article presents a protocol for seeding scarce population of cells using pipette-tips to droplet microfluidic devices in order to provide higher encapsulation efficiency of cells in droplets.

Pipet Ucu yöntemine damlacık mikrosıvısal platformlar tohum hücrenin temel

Amongst various microfluidic platform designs frequently used for cellular analysis, droplet-microfluidics provides a robust tool for isolating and ...